1. Field of the Invention
The present invention relates to nanocomposites, and, more particularly to amorphous carbon-boron nitride nanotube (BNNT) hybrids.
2. Description of Related Art
All references listed in the appended list of references are hereby incorporated by reference, however, as to each of the above, to the extent that such information or statements incorporated by reference might be considered inconsistent with the patenting of this/these invention(s) such statements are expressly not to be considered as made by the applicant(s). The reference numbers in brackets below in the specification refer to the appended list of references.
Utilizing the full mechanical capabilities of individual nanotubes is a primary research goal in nanotube reinforced nanocomposite materials. Most studies on structural applications of nanomaterials, such as carbon nanotubes (CNTs), have focused on attempts to improve dispersion in structural matrices to achieve or exceed the performance of state-of-the-art carbon fiber reinforced polymer (“CFRP”) composites. This approach has yet to yield mechanical properties that compete with CFRPs, the aerospace structural material of choice [10, 11], because CNTs have not demonstrated the load carrying capacity of carbon fibers due to poor intertube load transfer and physical defects created during processing and fabrication. Practical use of these nanomaterials requires creating stable and strong linkages between nanotubes without sacrificing their mechanical advantage. Cross-linking between shells via electron beam irradiation [12-15] and application of large compressive forces [16] have been studied and offer a viable approach to improve tube-to-tube load transfer and hence, mechanical properties. However, these approaches result in unwanted mechanical degradation and have limitations in scale-up for their applications to hierarchical macroscopic nanocomposite materials.
It is a primary aim of the present invention to use amorphous carbon (a-C) to form stable connections between the tubes using electron beam irradiation.
It is an object of the invention to provide a method for in-situ transmission electron microscope (TEM)-atomic force microscope (AFM) techniques which precisely position BNNT specimens and use electron beam radiation to deposit a-C to modify and join BNNTs one or more times.
It is an object of the invention to provide a method for joining BNNTs in which the a-C joint on BNNT structures is comparable with those of currently available structural fibers and films such as both CNT and BNNT yarns, carbon fibers, carbon fiber reinforced composites, both CNT and BNNT sheets, both CNT and BNNT composites and mixed composites of CNTs, boron carbon nitrides (BCN)s, and BNNTs.
It is an object of the invention to provide a method for a-C welding of BNNT structures which transfers load between the tubes for structural material designs.
Finally, it is an object of the present invention to accomplish the foregoing objectives in a simple and cost effective manner.
The above and further objects, details and advantages of the invention will become apparent from the following detailed description, when read in conjunction with the accompanying drawings.